Reading path
Where Self-Help Came From
Six books spanning a century that built the modern success industry — read in order, you can watch one claim mutate from character into thought into attraction.
These six aren’t a curriculum so much as a family tree. Read in publication order they show one idea — that your inner life sets your outer circumstances — being handed down, repackaged for a new audience each time, and getting steadily more generous about what it promises and steadily quieter about what it asks. Which is worth knowing before you pick up anything on the shelf they founded.

As a Man Thinketh
Start at the root. James Allen's 1902 essay is barely a book — a few thousand words arguing that circumstance grows out of character, and character out of habitual thought. Almost everything below is a louder version of this.

Think and Grow Rich
Then the one that made it an industry. Hill's 1937 bestseller keeps Allen's premise and attaches money to it: a desire specific enough to name a figure and a date, drummed into the subconscious until it becomes persistence.

Outwitting the Devil: The Secret to Freedom and Success
Now the sequel he wrote the year after, which sat unpublished for 73 years. Same six fears, same machinery — but staged as an interview with the Devil, and shipped in 2011 with a modern editor's annotations. Read it beside the record on Hill himself.

The Power of Positive Thinking
The claim goes to church. Peale, a Manhattan minister, rebuilds it in 1952 as faith plus repetition, and sells it to a mainstream that would never have picked up Hill.

Psycho-Cybernetics: A New Way to Get More Living Out of Life
Then it goes to the clinic. Maltz was a plastic surgeon who noticed patients whose faces he'd fixed still felt disfigured, and in 1960 recast the whole tradition as a self-image problem — the first version with a mechanism you can actually test.

The Secret
End where the lineage does. Byrne strips out the work and keeps only the wish, and the result outsold all of them. Once you've read the other five, you can see exactly which parts were dropped to get here.